SYNCHRONIZATION OF DEVICES IN A PEER-TO-PEER NETWORK ENVIRONMENT

• US 20130132501A1
• Filed: 09/24/2012
• Published: 05/23/2013
• Est. Priority Date: 11/18/2011
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Vandwalle, Pierre B., Hartman, Christiaan A., Stacey, Robert, Heerboth, Peter N., Thomas, Tito
• Granted Patent: US 9,473,574 B2
• Time in Patent Office: Days
• US Class Current: 709/208
• CPC Class Codes: H04L 67/104 Peer-to-peer [P2P] networks
• CPC Class Codes: H04L 67/1051 Group master selection mechanisms
• CPC Class Codes: H04W 4/08 User group management
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A system, apparatus and method for synchronizing devices in a peer-to-peer communication environment. Devices select a master to facilitate their synchronization, and rendezvous according to a schedule of availability windows broadcast by the master. Devices may attend some or all of the availability windows, during which they may send and receive unicast and/or multicast messages. Individual devices conserve power by being automatically synchronized instead of having to individually discover other devices and services, and can power off their radios without sacrificing discoverability. Synchronization and peer-to-peer communication as provided herein coexists with other device demands, such as Bluetooth® operations, infrastructure-based communications and so on.

Claims

1. Apparatus for synchronizing with multiple peer devices in a peer-to-peer communication environment, the apparatus comprising:

a processor;

a communication module for communicating wirelessly;

first logic executable by the processor to identify a sequence of availability windows having associated communication channels and associated times; and

second logic executable by the processor to discover the multiple peer devices during one or more of the availability windows.

2. The apparatus of claim 1, wherein the first logic is further executable by the processor to:

tune the communication module to a predetermined social channel; and

receive a synchronization frame broadcast on the predetermined social channel;

wherein the synchronization frame identifies the sequence of availability windows.

3. The apparatus of claim 1, further comprising:

third logic executable by the processor to power off the communication module except during the availability windows.

4. A method of synchronizing with peer devices in a peer-to-peer communication environment, the method comprising, at a first device:

detecting a synchronization frame issued by a first master peer device;

extracting from the synchronization frame information identifying a sequence of one or more availability windows, wherein each identified availability window has an associated communication channel and an associated time;

synchronizing with the first master peer device by attending a first availability window identified in the synchronization frame; and

during the first availability window, transmitting a communication to identify the first device to one or more of the peer devices.

5. The method of claim 4, further comprising:

exchanging electronic communications with a first peer device during the first availability window; and

extending the first availability window to continue the electronic communications.

6. The method of claim 4, further comprising, during the first availability window:

mutually discovering one or more peer devices.

7. The method of claim 4, further comprising, during the first availability window:

scheduling a rendezvous with one or more peer devices outside of the availability windows identified in the synchronization frame.

8. The method of claim 4, wherein the first device attends the first availability window by tuning a wireless communication module to the communication channel associated with the first availability window at the time associated with the first availability window.

9. The method of claim 4, wherein:

the synchronization frame is detected on a first channel; and

the communication channel associated with the first availability window is different from the first channel.

10. The method of claim 4, further comprising:

during the first availability window, receiving an additional synchronization frame issued by the first master peer device.

11. The method of claim 4, further comprising:

during the first availability window, receiving an additional synchronization frame issued by a peer device other than the first master peer device.

12. The method of claim 4, further comprising:

extracting from the synchronization frame one or more of;

selection metrics of the first master peer device; and

a master preference value of the first master peer device.

13. The method of claim 4, further comprising:

extracting from the synchronization frame metrics of a second master peer device to which the first master peer device is synchronized.

14. A non-transitory processor-readable medium storing instructions that, when executed by a processor, cause the processor to perform a method of synchronizing with peer devices in a peer-to-peer communication environment, the method comprising, at a first device:

detecting a synchronization frame issued by a first master peer device;

extracting from the synchronization frame information identifying a sequence of one or more availability windows, wherein each identified availability window has an associated communication channel and an associated time;

synchronizing with the first master peer device by attending a first availability window identified in the synchronization frame; and

during the first availability window, transmitting a communication to identify the first device to one or more of the peer devices.

15. A method of synchronizing multiple devices in a peer-to-peer communication environment, the method comprising:

at a first master peer device, issuing periodic synchronization frames identifying;

a sequence of availability windows for peer devices to rendezvous, each availability window being defined by a communication channel and a time;

selection metrics of the first master peer device reflecting a first master preference for maintaining the first master peer device as a master peer device; and

a stratum in which the first master peer device operates, wherein the stratum identifies a level within a logical hierarchy into which the multiple devices are organized; and

comparing the first master preference of the first master peer device with a master preference of another device, to determine whether the first master device is to continue operating as a master peer device.

16. The method of claim 15, wherein the periodic synchronization frames are issued on a different channel that the communication channel defining an availability window.

17. The method of claim 15, further comprising, at the first master peer device:

during the availability window, issuing an additional synchronization frame identifying an updated sequence of availability windows.

18. A network of synchronized peer communication devices, comprising:

a top master issuing top periodic synchronization frames identifying a first sequence of availability windows to be attended by peer communication devices synchronized with the top master;

a plurality of masters synchronized with the top master, wherein each master issues periodic synchronization frames identifying a second sequence of availability windows to be attended by peer communication devices synchronized with the master; and

a plurality of slave devices synchronized with the plurality of masters;

wherein a peer communication device attends an availability window by tuning to a specified channel at a specified time.